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Current burdens of faecally derived pathogens entering the environment through untreated human and animal faeces can lead to disease, through direct handling and through contamination of water supplies used for drinking and washing. Anaerobic digestion for biogas generation in rural households in Sub-Saharan Africa has the potential to reduce pathogen loadings to the environment through treatment of livestock manures and effluent from pit latrines. However, there are limited data available for its efficacy in Sub-Saharan Africa. We review evidence from around the world and consider its application to the Sub-Saharan African situation. [ABSTRACT FROM AUTHOR]

We previously demonstrated that the survival time of BALB/c mice challenged with Toxoplasma gondii RH strain was prolonged by immunising the mice with a eukaryotic vector expressing the protein ROP16 of T. gondii . Building upon previous findings, we are exploring improved vaccination strategies to enhance protection. In this work, a novel recombinant canine adenovirus type 2 expressing ROP16 (CAV-2-ROP16) of T. gondii was constructed and identified to express ROP16 in Madin-Darby canine kidney cells (MDCK) cells by western blot (WB) and indirect immunofluorescence (IFA) assays. Intramuscular immunisation of BALB/c mice with CAV-2-ROP16 was performed to evaluate the humoral and cellular immune responses. This vaccination triggered significant humoral and cellular responses, including ROP16-stimulated lymphoproliferation ( P < 0.05). Compared to control groups, the CAV-2-ROP16 immunised mice had high production of IFN-γ, IL-2 and IL-12 ( P < 0.05), with a predominance of IgG2a production, but not IL-10 ( P > 0.05), revealing that a predominant Th1-type response had developed. The cell-mediated cytotoxic activity with high levels of IFN-γ and TNF-α was significantly increased in both CD4 + and CD8 + T-cell compartments in the mice immunised with CAV-2-ROP16 ( P < 0.05), compared to three control groups. In addition, when immunised mice were challenged with the RH strain of T. gondii , they showed a significantly increased survival rate (25%) 80 days post infection compared with control mice that all died within seven days ( P < 0.05). The 25% protection rate elicited by the recombinant virus CAV-2-ROP16 has not been achieved in the field of anti- T. gondii vaccination until now. Our work presents the successful use of recombinant virus CAV-2-ROP16 in vaccination protocols to protect against intraperitoneal challenge with the virulent RH strain of T. gondii . This system was shown to be extremely efficient in eliciting humoral and cellular immune responses that led to a significant improvement in survival time in mice. [ABSTRACT FROM AUTHOR]